Regional inequalities in maternal-level under-five mortality in Ethiopia: evidence from the 2019 Mini-DHS using multilevel negative binomial and Bayesian models

Despite substantial improvements in child survival globally, marked regional inequalities in under-five mortality persist in Ethiopia. This study examined subnational disparities in maternal-level under-five mortality intensity using nationally representative 2019 Mini-Ethiopian Demographic and Health Survey (Mini-EDHS) data. A cross-sectional analysis was conducted using data from 3,892 mothers with 14,619 live births and 332 maternal-level under-five deaths. Maternal-level under-five mortality intensity was modeled using multilevel negative binomial regression with the number of children ever born included as an offset. Bayesian hierarchical models were fitted to assess the robustness of the findings. Significant regional disparities were observed. Compared with Tigray, maternal-level under-five mortality intensity was higher in Somali (IRR = 2.85; 95% CI: 1.39–5.84), Benishangul-Gumuz (IRR = 2.71; 95% CI: 1.33–5.51), Gambela (IRR = 2.81; 95% CI: 1.37–5.76), Dire Dawa (IRR = 2.20; 95% CI: 1.02–4.74), and Harari (IRR = 2.28; 95% CI: 1.07–4.86). Birth order was inversely associated with maternal-level under-five mortality intensity (IRR = 0.82; 95% CI: 0.78–0.86), likely reflecting fertility-selection effects rather than a causal relationship. Findings were consistent across frequentist and Bayesian analyses. Substantial regional inequalities in maternal-level under-five mortality intensity persist in Ethiopia, particularly in pastoralist and emerging regions. These findings highlight the need for geographically targeted, context-specific strategies to strengthen maternal and child health services and reduce persistent subnational disparities.